You are (I think) confused and have this backwards. We consider how much energy/speed we have to give something to throw it up to arrive, at rest, at a maximum height of e.g. 25,000 miles (which is the energy/speed it will have if it lands when dropped from there, at rest. To throw it up HIGHER you have to throw it FASTER with MORE energy. Gravitational POTENTIAL ENERGY is actually LESS in proximity -- greater in magnitude but (by convention) MORE NEGATIVE.
Specifically, if we drop one kilogram from rest 25,000 miles away -- say 6 Earth radii (R_e \approx 4000 miles) then its initial total energy is E_i = U(R_e)/6 or
E_i = U(R_e)/6 \approx -10 MJ = K_f + U(R)
When it lands, energy is conserved, so:
E_f = E_i = K_f + U(R_e) = - 10 MJ
K_f = E_i - U(R_e)
Or it hits with 54 MJ instead of 64 MJ
4.4 million miles is so many that E_i = U(R_e)/1100 \approx - 64 KILOjoules per kilogram. Then:
K_f = E_i - U(R_e) \approx 64 MJ, the initial total energy is so small it doesn't change either of these digits or (for that matter) the next two. 4.4 million miles is "infinity" as far as this estimation is concerned.
So here's a serious answer. Gravitational potential energy has the form U = -GMm/r where r is the distance from the center of the earth. Practically speaking, this means that a kilogram of mass sitting on the surface of the Earth has a gravitational potential energy of -GMm/R where R is the radius of the earth and m = 1. If you work out the arithmetic, this is NEGATIVE 64 MJ give or take a hair (GM/R = gR = 6.4x10^7 J).
Total energy is potential energy plus kinetic energy: E = K + U with K = 1/2 mv^2. If you are "infinitely" far from Earth and at rest relative to the Earth, the kilogram of mass has a total energy of zero. Energy is conserved, so as it falls towards Earth (gravity doing work on it to speed it up) its potential energy decreases (because more negative) and its kinetic energy, which is strictly non-negative, increases in order that the total energy REMAINS zero. When it hits, therefore:
K = -U = 64x10^7 J = 64 MJ
"Infinity" here is just any distance that is very large relative to the radius of the Earth so that U is "small" relative to this collision energy and hence an unimportant correction.
Note well that nothing stops our kilogram of mass from being THROWN in from infinity with MORE than zero initial kinetic energy. Indeed, we expect falling asteroids to nearly always start with some speed relative to the Earth and a total energy relative to the Earth GREATER than zero, as they are "unbound" by Earth gravity and in what is called a hyperbolic trajectory when they hit. This means that if they miss, they keep on going and don't eventually come back or end up trapped in orbit around the Earth. It also means that they can hit with a kinetic energy strictly greater than 64 MJ or (solving for the speed of the collision) a speed strictly greater than 11.2 km/sec.
If you really want to understand this further, here is a physics book where it is explained, between chapters 3, 4 and 12:
Asteroids will hit the Earth (if at all) at LEAST at 11.2 km/sec, as they have greater than escape energy relative to the Earth's gravitational field. That's 11.2 kilometers per SECOND, or a bit over 40,000 kilometers per HOUR. The energy released is greater than 64 million joules per kilogram of rock (escape energy). So if you take a (say) 2.5 km ball of rock (5 km in diameter), roughly estimate its mass as 4 times r^3 you get 4 e+18 joules. Convert this to tons of TNT and you get roughly a teraton. The total explosive energy of the entire nuclear arsenal of the Earth is less than 7 gigatons (including reserve weapons -- only around 1 GT is on delivery vehicles almost all of this belonging to the US and Russia). The biggest explosion in recorded history was the explosion of Tambora in 1815, estimated at 33 GT. This is then equivalent in crude terms to over 100 times the entire global arsenal nuclear and conventional, or over 30 times the explosive power of the largest explosion in recorded history, one that altered global climate for close to a decade. Or GREATER.
I'm not sure "hit by a bus" is an apropos metaphor.
Even worse, pretty much every science fair project has to have a conclusion to get anywhere. Teachers don't let kids run an experiment where the conclusion is that the test didn't have any findings that support accepting or rejecting the hypothesis. That is not only a perfectly acceptable result in science, but a very good one to find.
Hear hear! I'm giving up a chance to mod you up because that isn't sufficient. This is all by itself one thing that is wrong with STEM training from the beginning. One cannot just build a telescope or Tesla coil -- both pretty ambitious, amazing projects for any science fair -- you have to have a HYPOTHESIS and you have to PROVE IT because, I dunno, null results are so boring and indistinguished that they will never win. Kids learn at Science Fairs that if they don't prove their hypothesis no one will look twice at their work no matter how nifty and then we wonder why twenty years later they are falsifying data or engaging in data dredging or cherrypicking to get publications to get tenure or keep a grant. We also wonder why we get a steady string of crappy papers on things nobody really cares about -- but which have clear targets likely of success -- instead of a few bold papers where the researchers took risks at finding nothing equal or greater to the chance of finding something. Those big, risky topics are career killers unless you are fortunate enough to have nearly independent "means" as research support.
Don't get me wrong -- evidence is key to directed Bayesian beliefs, and science should teach the importance of evidence. But the entire Enlightenment wasn't driven by hypotheses eventually supported by evidence. It was driven by bold, amazing new instrumentation -- for example, microscopes and telescopes -- that opened up a Universe of new data at the macrocosmic and microcosmic levels Pure observation based on these new instruments eventually LED to hypotheses, and as time passed the successful hypotheses were woven into an ever tighter tapestry of evidence supported beliefs connected to other evidence supported beliefs and the scientific worldview. This was equally so for most of the initial work done with electricity and magnetism -- people built nifty generators and studied the effects of electrical currents and then, eventually, built a mathematically rich explanation of the collective set of observations.
Can you imagine having to formulate Maxwell's Equations as a hypothesis ALL AT ONCE and then going into a laboratory to try to verify them? Or even something simpler, like Coulomb's Law? Hell no! Coulomb may or may not have suspected that electrostatics were going to be "like" gravitation (although Newton had no compelling reason to choose 1/r^2 for gravitation in the first place, lacking Gauss's Law or any equivalent thereof) but the evidence in favor of it was compelling and immediate.
Cutting edge real science has observations leading hypotheses -- as, if you think about it, it usually should -- more often than not. But high school science teachers and the founders of the whole idea of "science fairs" have completely lost track of this in their eagerness to teach The Scientific Method as religion instead of a practical methodology that -- eventually -- needs to be satisfied.
Ultimately it is an empirical question but it is an unusual one. The problem with looking only at locality in a single direction of time flow is that the underlying microdynamic propagators are (without exception as far as I know) reversible in time. My favorite example of this is in classical electrodynamics, where we CHOOSE to use retarded propagators, but where one can equally well formulate things in terms of advanced propagators and where Dirac did an amazing job of deriving radiation reaction theory using a mixture of advanced and retarded propagators (further supported by Wheeler and Feynman and the perfect absorber derivation which in turn is connected to Lindblad and master equation formulations of quantum theory).
This is where IMO it is very difficult to understand Bell's theorem. It seems to require forward (retarded) time only, but if one allows for advanced time as well as retarded time both operating simultaneously, the paradoxes disappear. It becomes literally impossible to hide the future state of the ultimate absorbers of any e.g. photons emitted from a quantum entangled system from the emitting system -- the entire path through all intermediate filters is NOT information that is unavailable to the emitting system. The real problem is that that the time evolution of a closed quantum system begun in a stationary state is stationary, period, from a very fundamental theoretical level. The "paradoxes" seem to arise when we try to create "observers" that are one part of the total system, "systems" that are another part of the total system, and a "bath" made up of everything else that is in an almost completely unknown state. EVERYTHING is fully quantum entangled, ALWAYS. But when you split things up, pseudoentropy appears as one is forced due to ignorance of boundary conditions and intermediate time evolution of the whole to use a statistical (and hence classical or at worst semiclassical) description of both bath and observer.
It's pretty easy for me to believe that the effective pseudoentropy of Universe-(sub)system is so absolutely enormous that the quantum description of any subsystem (averaged) is going to look "random" in accordance with Bell's inequality but not, in fact, be random. It isn't a matter of local hidden variables, it is a matter of unknown state variables in everything else coupled to the system by ordinary interactions.
My journey has been longer, padawan. But you are mistaken: we do have both hover cars and hover boards. They are just expensive and dangerous. What did you expect? Antigravity? Suspension of the laws of physics? Personally I was hoping for antigravity capable of floating a car-sized mass with a tiny trickle of current, reorientable as a gravity-based drive. But somewhere back in the 70's and early 80's I finished my physics degrees and alas, there was no plausible antigravity anywhere to be found. Still isn't. Especially one that would work on a first-law-violating trickle of current.
that required a "trick" to keep moving, but ten seconds of examination and experimentation revealed that they are not. And gyroscopic wrist trainers are already pretty boring, but at least there you have to "do" something and you can fix them up with pretty lights and so on too. Spinners aren't even a good meditation aid -- they demand exactly the wrong kind of attention to keep going and they are not a useful focus.
If something has a cause, then it can be predicted and patterns can be identified. It is not random.
Except that there are phenomena that cannot be predicted. Even ones we know are not really random. Then there are quantum phenomena that MAY be really random. You are making a religious statement when you assert Universal causality as a definite truth instead of a conditional probability. And lack of evidence is not evidence of lack -- the best you can say is that it might make something less probable within certain bounds.
I agree that the Universe PROBABLY is causal and in a zero entropy state, because we have little definite evidence otherwise (time-irreversibility of things like Kaon and B decay aside, a few experiments that claim to demonstrate "true" quantum randomness aside). But according to science this is an empirical question, not a religious one. You might as well assert that as far as we know, it IS possible for true randomness to exist.
On the empirical note, if you are presented with a string of data, perform any and all tests on it that you like, and cannot prove that it is NOT random, what exactly is that evidence of? Please do not invoke religion in your answer such as a belief in causality, as that just begs the question. That's precisely what you are doing if you assert that quantum phenomena at a certain scale are not random. Maybe not, but we have no model that predicts them, we have theories that suggest that no model CAN predict them, when we examine them for randomness they appear random. The arguments (such as the arguments that lead to the Master Equation description of quantum phenomena) that allow for it to be otherwise are difficult and while they may be correct, it is far from certain (empirically) that they are.
As I posted above, we do not know this. IF you accept e.g. the holographic MODEL of string theory, then there is no entropy even at the quantum level. On the other hand there are plenty of articles in QFT that discuss the possibility that QFT is truly irreversible at some level so the direction of time is not just a consequence of entropy.
It is perfectly fine to think that one or the other of these is "more likely" to be true on the basis of what one knows or guesses, but because physics is not religion it is not appropriate to state that there is not random as a proven fact, that the entropy of the Universe is zero and there are no true entropy sources. Ultimately this, like everything else, is an empirical question.
Personally I agree with you and think that whether or not the holographic model per se is correct, QFT is probably reversible and that the Universe is in a zero entropy (definite) state with no "outside" source of entropy to make it non-deterministic on the basis of internal dynamics alone. But in the end, experiments talk, bullshit walks and even the sexiest theoretical model is bullshit until it is confirmed by experiment.
There are three meanings of the word "random" referring to a generator in this context:
a) Unpredictable. b) Empirically satisfying all of the decorrelation properties of a random number sequence -- on average uniform in all bit patterns, on average lacking correlations at all lags (and hence non-periodic) and on all N-dimensional hyperplanes for all N, etc. c) Both.
All that is asserted here is that they have a thermal noise generator that satisfies a). Big whoop -- thermal noise generators (and hardware generators in general) are commonplace: https://en.wikipedia.org/wiki/.... However, thermal noise and so on are often "colored" or "biased" -- they produce fluctuations that are unpredictable but it is almost impossible to get the noise to produce a string of e.g. 0's and 1's that satisfy b). One then is stuck using the unpredictable noise to randomize a pseudorandom number generator (for example, by xor'ing the two together) that produces a bit string that has the right uniformity and decorrelation properties but does so from an internal state that, if known, makes the string produced predictable.
AGAIN this sort of thing is pretty commonplace. Sources of "entropy" as in unpredictable activity are common enough and so are high quality pseudorandom number generators. The major problem then is rate. Few of the hardware generators can produce entropy FAST ENOUGH to keep up with a PRNG, so getting a source of "true random numbers" that is fast enough to use in e.g. Monte Carlo is not easy, and most people don't bother to try. Having a handful of unpredictable numbers suffices for e.g. encryption and that's really where this is headed.
I would wax poetic on the fact that EVEN thermal noise is probably not truly random; it is random the way a coin flip is random or, for that matter, the way a PRNG is random. The outcome of a coin flip is unpredictable only because we don't flip the coin with a precise knowledge of its state and the state of the flip environment and because we perhaps cannot integrate its equations of motion precisely enough from what knowledge we do have, but it is deterministic, hence not really unpredictable. Classical thermal noise is no different than a bunch of flipping coins bouncing around -- again deterministic but with lots of unknown state information. "True" random is a term that should probably be provisionally reserved to AT BEST quantum "coin flips", although in the master equation approach to resolving the state of a quantum "coin", the true origin of randomness is seen STILL to be the process of taking the trace of the surrounding environment, which is if you like the filter resolving the flip. That trace introduces "entropy" in the form of lost phase information and averaging over energy distributions that appears as unpredictability in the outcome, but if one views the "coin" AND the surroundings as a single quantum system its quantum trajectory is again deterministic. Randomness in quantum filtering experiments comes from the fact that the measuring apparatus that does the filtering must resolve it in a classical was with its quantum entangling and phases in general unknown and averaged over.
If one buys the holographic model in string theory (or plain old quantum theory as it is currently structured) the Universe is in a zero entropy state and there are no sources of "real" entropy. In this case there can BE no "true" random number generators. Whether or not nature is capable of generating true random numbers from some source other than our ignorance of state is an open empirical question.
...for a narrow time window. The moon gets a bit more than 3 cm farther from the earth every year due to rotational energy coupling through the tides. We are in the comparatively narrow time window (geologically speaking) where the moon and the sun have roughly the same angular width as seen from the earth (depending on just where the moon is in its elliptical orbit and where the earth is in ITS elliptical orbit). Wait a million years or so and the moon will produce only annular eclipses.
It's like Polaris as the North Star. Fiction writers like to portray Jesus or Moses or Caesar looking north and waxing poetic about the Nort Star, but a couple of thousand years ago Polaris wasn't the North Star, we had no North Star. Even a few hundred years from now it is going to be making circles instead of behaving like a fixed point on time lapse photographs. Sigh.
A point I was making way back then, when it wasn't even cost effective. If the US had invested (say) 20 or 30 billion a year directly into photovoltaic power starting back in the second Iraq war, let alone the first, by guaranteeing a market they would have singlehandedly created the solar cell manufacturing capacity to utterly dominate the world marketplace, they would have dropped prices at 2-3 times the rate they ultimately dropped anyway, and by now we would made the Middle East and its oil supply even more irrelevant than they are rapidly becoming.
This is one thing nobody is even noticing, even though it is ongoing. We're in the last decade where oil is going to be "valuable" as a fuel. Saudi Arabia is going to undergo a profound, deep, economic crash. Most of the Middle East and other oil producing countries (and companies) are going to be right in there crashing and (not) burning. Oil will be a lubricant and important chemical stock, but burning it for the most part will stop making sense and existing stocks will plunge in price. One major casualty of this will be Russia. Tillerson is such an appallingly transparent choice for SecSt, as he personally will be another. At this point it is too late to put the genie back into the bottle, even though the government by its stupid choices as kept it jammed in there as long as it possibly could, as we are at the pivotal point where one can take a house off grid "forever" for less than the cost of a high-end car in most of the US (the lower states, certainly). And it is only going to get cheaper. A lot cheaper. Fast. Much faster than the pundits themselves seem to realize.
I expect to see ten cents per watt-hour of high-end battery storage well before 2020. A 50 KW-hour whole house battery plus regulator for $5000, sized to fit easily into a dedicated function closet. Even just used as a whole house UPS and energy brokerage tool you'd probably break even on that -- buying electricity and charging at cheap/low demand night to run your AC in high-demand/expensive daytime, being invulnerable to up to 24 hour line outages during storms, buffering line surges -- but you can ALSO use as much or little renewable capacity as you can afford to charge it up and reduce line demand. We're teetering on 10 year amortization right now, but we'll see 7 year amortization by 2020. Borrow the money, install a full off-grid system (that sells back to the utility if there is surplus, sure) and pay for the whole thing in 7 years while dropping your monthly power bills even while paying it off.
At that point, the government is irrelevant except to get out of the way and not try to prop up the doomed utilities by imposing legal obstacles.
So a better way to put it is that it is order of one CUBIC mile. You can make the cross-section smaller by making the stack higher or vice versa. Area measures make sense for solar cells. They don't for batteries.
They REALLY don't for batteries that are supposed to back the whole solar grid for the US. Those batteries generate heat as they operate -- charging or discharging. If you actually built a solid battery a cubic mile in volume (say) heat losses scale like the outer radiating surface, heat production scales like volume. Even very modest losses would rapidly raise the temperature of the center of the cube to the point where (resisting the temptation to say something hyperbolic such as "thermonuclear fusion occurs" the "temperature of the surface of a star" etc) but honesly, the latter is probably true -- 6000 K would be quite reasonable if it weren't for the fact that the entire stack would melt and fail long before that.
If you build the batteries of a size that can self-cool via convection/radiation -- no active cooling required with larger radiators or heat exchangers -- and assign them a reasonable margin of empty space around so that they don't overheat -- they would occupy far more than a cubic mile, and with an average height order 1 meter, they'd occupy tens to hundreds of miles square of total area. That is hundreds to thousands of square miles
So let's forgive EM his usual hyperbole and sales pitch exaggerations. Nobody is going to actually build this in this way, and as noted above, this argument is so old it is positively ancient. The critical number, which he omits, is that if we assume that the US uses roughly 10 terawatt-hours/day, and assume that we can generate this with around 3 terawatts of of (peak) solar capacity plus storage in an average day, and solar power costs roughly $1/watt (peak) installed, then it would cost roughly 3 trillion dollars to install all of this electrical capacity at current prices, give or take a factor of two -- there would be economies of scale to a massive project like this, for example, but the duty cycle (average) of the cells is arguable and average solar constant as a function of location is variable, so one might need twice this capacity to have some margin. With a population of three hundred million people, we could buy this for ten thousand dollars each, and the investment would be amortizable against the savings in electrical energy costs already extant (typically amortizes in 10 or so years of a 20+ year expected lifetime).
This lets one instantly at least estimate scenarios. $1000/person is $300 billion. If we invested $1000/person/year, at a cost of $300 billion total, 100% provided by taxes (as poor people cannot afford $1000/person/year, and rich people actually consume a lot more on average of the energy this would generate to boot, both personally and in their corporate rents and ownerships) we would completely remake the country's infrastructure in ten years, very likely getting to the point where all we'd need is bridge power from a network of e.g. nuclear power plants and a gradual investment in increased and replacement capacity (generation plus battery backing) to never have to actually BUY electricity again. We could actually charge "energy taxes" at cost of this maintenance plus new growth at cost based on individual and corporate consumption and enjoy the closest thing to free energy solar can deliver at any given level of technology and development. We could charge energy taxes AS our tax basis, eliminate income taxes entirely, and distribute the cost burden of government proportional to energy consumption, both per capita and corporate. If you want to go off grid, you won't have to pay taxes, except that anything you buy or use that is even MADE with energy will have a hidden tax in it. Maybe it would work, maybe not, but it is an interesting idea, akin to a "gold standard" except that the unit of commerce would de facto be the joule (or KW-hour, or whatever).
I WAS kidding, right? Although SF (e.g. Oath of Fealty, Niven and Pournelle) speculates on towing medium sized icebergs for just this purpose (providing fresh water in a water-scarce zone). But yeah, an iceberg the size of Delaware, or whatever metaphor for a 50x40 mile chunk of area many meters thick you would prefer to use, would be rather expensive to move.
What will be interesting will be if it floats north. It's big enough to significantly cool a good sized chunk of sea surface as it melts, at a guess. This, in turn, might affect many things in good and/or bad ways. For example, interrupting or diverting the thermohaline circulation would be "interesting"...
Fixed that for ya. I assume that you mean the end of the Wisconsin glacial epoch, give or take a Younger Dryas. Funny how human civilization rose during a period of intense global warming... (and the melting of an ice layer several kilometers think that covered most of Canada and much of the northern US at the time...).
Archeological studies suggest that there was a serious political conflict back then with the "whites" -- a combined ecological-political movement that opposed the (obviously human induced) climate change -- and the more progressive "greens" who viewed climate change as an obvious opportunity to make a huge profit on suddenly desirable real estate, at least until it was swamped in the 100-odd meter sea level rise associated with the change.
Sadly, throwing entire populations into volcanoes and cutting the hearts out of thousands of slaves proved to be inadequate to prevent the climate change, although the Younger Dryas was evidence that if the population of the world were just a LITTLE larger at the time, mass genocide might have accomplished it, and we'd still have woolly mammoths along with woolly socks.
So, let's tow the iceberg to the Sahara, and use it to irrigate and cool the desert, and in the process bind up much of the water in an extension of water cycle to lots of surface area that currently does not participate. No? Just because it will cost a trillion dollars or so? When did costs become an important part of the climate narrative?
As I sit here, preparing to teach electricity and magnetism (having corrected a minor error in the electrodynamics book I wrote to help supplement Jackson while teaching graduate electrodynamics, I do find it interesting that you ignore the actual algebra I put into my previous reply and instead attempt to argue using logical fallacies. Most of the Wikipedia articles on physics are, in fact, pretty damn good, and photons are considered "massless" particles in pretty much every physics textbook that considers them, where yes, the term refers to their rest mass but also where there is no real point in considering them to be massive in any other context and some serious inconsistencies to deal with when one tries to treat e.g. h\nu/c^2 as if it is a "mass" as far as gravitation is concerned.
And yet another article (containing many links to actual references) on the standard model in which the photon and gluon are indeed massless particles is here:
again with many references, such as almost any textbook in physics that addresses the issue at all.
Perhaps you could stop accusing people of ignorance and asserting that WIkipedia is written by idiots and instead provide an actual reference to a textbook or article in a peer-reviewed journal where it is claimed, with evidence, that it makes sense to associate a mass with a photon, even in the context of gravitation (where there is indeed a gravitational interaction with its ENERGY).
E = \gamma m_0 c^2 for massive objects, where m_0 is their rest mass. Alternatively, E^2 = m_0^2 c^4 + p^2 c^2. In neither case do electromagnetic waves have mass. Indeed, for electromagnetic waves (or photons) E = pc because m_0 = 0. This does NOT mean that E = \gamma m_0 c^2 = pc = m c^2 with m_0 = 0 and \gamma = infinity (where you effectively have to assert that 0 * infinity = 1) so that you can conclude that p = mc for electromagnetic waves for some meaningful/useful definition of mass. Note well that one cannot just assert that 0*infinity = m (for some specific, varying, value of m!) in the first place as a useful step in algebra, and there is no good way to take limits of m_0 \to 0 and v \to c to define an "asymptotic" massive electromagnetic wave of photon, at least that I've heard of.
Either way, U(1) symmetry requires the photon to be massless, classical electromagnetic theory requires electromagnetic waves to be massless, experiments have restricted the (rest) mass of photons to be less than 10^{-18} or so kg, and \gamma is not a meaningful construct for objects with zero rest mass that propagate at the speed of light.
Finally, to rebut the various people who WANT to make m = p/c for a photon or assert that it is not a massless particle, I quote the wikipedia page for massless particles:
In particle physics, a massless particle is an elementary particle whose invariant mass is zero.
That is, by definition the invariant mass of a photon is zero -- it is a massless particle. In fact, it is the first example of a massless particle given on this page, along with gluons and gravitons.
So please, can we stop accusing people who assert that the photon is massless of being ignorant or stupid or not understanding physics. If anything, quite the contrary.
700 large scale solar facilities around the state. What they are doing in other states I do not know, but in NC they are literally building new ones all the time. Note this:
NC is indeed number two in the national rankings in installed capacity as of last year, behind California and (perhaps surprisingly) ahead of near-desert states like Arizona, and most of this is Duke Power.
I reiterate: The Koch brothers have a specific agenda that is (as far as one can tell) the active suppression of democracy and the establishment, no, that's not fair as it's already there, the rapid growth in the power of an oligarchy. The energy companies in general, however, don't give a rat's ass what is the source of the energy they collect or release and redistribute, as long as they make a good profit from it. Solar is profitable, and about to become the most profitable, by far. So it doesn't matter what one does to "free up coal" or reverse carbon restrictions. Nobody is going back to (substantial new capacity in) coal in the US, although it may be decades before the grid can function without it.
Hey. don't pick on Duke Energy. NC is something like second or third in the nation in terms of total solar installation, and Duke Power is installing them pretty much everywhere. It is getting difficult to drive a hundred miles on major roads without seeing at least one solar farm off to the side of the road.
You are mistaken if you think that solar energy somehow costs the big electrical power companies profits. Quite the contrary, quite the contrary. PRIVATE solar rooftops might one day cost them profits, but solar that they install themselves makes them money. It is cheaper and easier to finance incremental installations of solar than it is to permission, finance, and build pretty much anything else.
--If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
Hmmm, interesting analogy. I don't think I agree. If construction were like programming, many buildings would have corridors that wind through the building with no entrances, it would have others with one way doors that you enter on the ground floor that take you through corridors with no exit to the top floor and exit through a one way door into thin air, it would produce buildings intended to function as a public library where the books have to be brought up, one at a time, from a basement filled with rooms indexed with the first word of the title and shelves indexed with the second stored in the order of the third word per shelf, for books with three or more words in the title. An entire second layer of basement would contain similar rooms indexed by the first letter of the author's name, etc, where the only items in card catalogs are the titles (hence first three words) in each author's name. An incorrectly fitted lock is more like a syntax error or typing error in a program -- comparatively easily found and corrected. Even if the lock is the primary entrance -- so it DOES block the use of the building -- the building doesn't "crash" as in have to be rebuilt, it just needs to have the lock fixed so that the building can be used.
In other words, there are plenty of places where the analogy does work. If you build a building with inadequate structural members, it might WELL come crashing down and have to be redesigned and rebuilt. If you build a building that is too small or too poorly designed to fulfill its primary function, whether it is as a residence or business or manufactory, you might need to tear down and start again, or do "extreme remodelling". All of those ARE features of coding as well.
I'd be more inclined to say that construction, or engineering in general, are a lot more like coding than not like it. Engineers build machines, or buildings, or bridges, out of structural elements that have properties, purposes, and that follow a certain logic. Coders build "machines" out of words. Special words, no doubt -- words that are structural elements with properties, purposes, and that follow a certain logic -- but words. That's the main difference.
To bring the (gentle, I hope) philosophical rant above back OT, serious coders are those that build their first machine out of words and then say to themselves how cool was that! At that point, to my own direct experience, you can't really stop them, especially if they learn that they can get material rewards for doing it as well. They will teach themselves what they need to know to pursue their (a)vocation, they will scrounge resources, they will stay up late (the only time you can code is late at night when all of your life 'distractions' have gone to bed:-), neglect their personal hygiene, and start drinking Jolt Cola to maintain their edge when they have to function in the "real world" on four or five hours of sleep in order to get 6 to 8 uninterrupted hours to code.
Personally, I think that the death of the US coder was caused by Windows and the various post-Mac Apples. PC-DOS provided a built in path for computer owners to start to write programs -- the original IBM PC has BASICA in ROM so you couldn't own a computer without owning at least one programming language in its own "development environment". BASICA got dropped from ROM as clones appeared, but it was replaced by "turbo" compilers that were cheap IDEs that anybody could buy (and did) driven by the fantasy of writing a game or killer app for the platform. Then Windows came along, and it was no longer easy, or cheap to write a program with graphics. This raised a huge barrier between the kids who might have become hackers/coders and actually doing so. At this point NO laptops or desktop computers sold with pre-installed Windows have anything like programming support.
No, it's just that well over half of us live in an enormously neurotoxic environment -- heavy metals in the water and air, food additives, insecticides, hormones, and antibiotics in the food, radioactives in the buildings and soil leftover from the era when we deliberately exploded nuclear bomb after bomb upwind of our population centers and farming regions. Then throw in Television, to take the brain-damaged children and ensure that they never even have to learn to read properly to be entertained at the same time they learn that entertainment is sitting passive (and has no intellectual challenge whatsoever in 95% of what is considered "entertaining"). Feed those children fast food with a huge salt load, sugar load, and a lack of actual nutrients so that -- given their sedentary entertainments -- they all are slightly overweight as children and blossom into openly fat adults long before "their time", impacting the blood supply to their brains. These children are taught -- explicitly taught -- not to think too critically from when they are far too young to resist, as a part of learning a religion that was literally invented and perfected to make a slave population content with their lot and unwilling to act to change it in an enormous slave-based empire in the fourth century BCE and that has done its work superbly (both functions -- elimination of critical thought and contentment with slavery) forever after. To finish off the job, put them in public schools with teachers that "Don't know where Malta is", being taught math by people who got a B- in calculus in college (if they went to college) from a textbook selected by a committee whose sole virtue is that it MIGHT help teach the students to balance a checkbook by the time they get out of school -- if there were any such thing as a checkbook any more.
Is it any wonder that at the end of this, you end up with young adults that think that the National Enquirer and Globe are the best sources of news and who vote for a billionaire liar serlal philanderer as president as being the best possible choice for freeing them from all of the massive corporations (including his) for whom they are a nearly perfect source of cheap labor? Note that it isn't any one of these things, or two of these things -- people can shrug off malnutrition, they can get past a terrible education -- it is literally damaged brains (probably in utero) as evidenced by the steady rise in ADD, ADHD, anxiety disorders, suicides, and more among the young and young adults, TOGETHER with a 60% or better terrible education with poor teachers and miserable textbooks, the elimination of reading as the primary form of "fantasy" entertainment (fun obtained from something other than getting up and doing something outdoors, with others) so that they cannot easily teach themselves, an information stream provided for entertainment that could cause brain damage (of sorts) in full grown adults, etc.
We shouldn't forget the impact of PTSD and rampant cigarette smoking, alcoholism and drug abuse among the young (including the very young) as well. At least those are things that the US doesn't have a near-monopoly on. The amazing thing is that even with all of this, a remarkable number of children grow into functional and even intelligent, ambitious, competent young adults. And we make up for many of the losses by attracting the best and brightest people from all over the world to immigrate and fill in the positions it is difficult to fill out of our general population, and it usually takes a generation or two for the genetic and cultural/moral decay to set in.
As for the Russians -- it is easy to see why they become hackers etc. A large chunk of Russia is too dark and too cold to go outside in winter at times that they aren't in school. Kids therefore have to entertain themselves indoors for months at a time at least during the winter. Russian TV sucks and is a lot sparser than US TV, and once they've read all of the books in the house, nothing is left but the computer(s). The r
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You are (I think) confused and have this backwards. We consider how much energy/speed we have to give something to throw it up to arrive, at rest, at a maximum height of e.g. 25,000 miles (which is the energy/speed it will have if it lands when dropped from there, at rest. To throw it up HIGHER you have to throw it FASTER with MORE energy. Gravitational POTENTIAL ENERGY is actually LESS in proximity -- greater in magnitude but (by convention) MORE NEGATIVE.
Specifically, if we drop one kilogram from rest 25,000 miles away -- say 6 Earth radii (R_e \approx 4000 miles) then its initial total energy is E_i = U(R_e)/6 or
E_i = U(R_e)/6 \approx -10 MJ = K_f + U(R)
When it lands, energy is conserved, so:
E_f = E_i = K_f + U(R_e) = - 10 MJ
K_f = E_i - U(R_e)
Or it hits with 54 MJ instead of 64 MJ
4.4 million miles is so many that E_i = U(R_e)/1100 \approx - 64 KILOjoules per kilogram. Then:
K_f = E_i - U(R_e) \approx 64 MJ, the initial total energy is so small it doesn't change either of these digits or (for that matter) the next two. 4.4 million miles is "infinity" as far as this estimation is concerned.
So here's a serious answer. Gravitational potential energy has the form U = -GMm/r where r is the distance from the center of the earth. Practically speaking, this means that a kilogram of mass sitting on the surface of the Earth has a gravitational potential energy of -GMm/R where R is the radius of the earth and m = 1. If you work out the arithmetic, this is NEGATIVE 64 MJ give or take a hair (GM/R = gR = 6.4x10^7 J).
Total energy is potential energy plus kinetic energy: E = K + U with K = 1/2 mv^2. If you are "infinitely" far from Earth and at rest relative to the Earth, the kilogram of mass has a total energy of zero. Energy is conserved, so as it falls towards Earth (gravity doing work on it to speed it up) its potential energy decreases (because more negative) and its kinetic energy, which is strictly non-negative, increases in order that the total energy REMAINS zero. When it hits, therefore:
K = -U = 64x10^7 J = 64 MJ
"Infinity" here is just any distance that is very large relative to the radius of the Earth so that U is "small" relative to this collision energy and hence an unimportant correction.
Note well that nothing stops our kilogram of mass from being THROWN in from infinity with MORE than zero initial kinetic energy. Indeed, we expect falling asteroids to nearly always start with some speed relative to the Earth and a total energy relative to the Earth GREATER than zero, as they are "unbound" by Earth gravity and in what is called a hyperbolic trajectory when they hit. This means that if they miss, they keep on going and don't eventually come back or end up trapped in orbit around the Earth. It also means that they can hit with a kinetic energy strictly greater than 64 MJ or (solving for the speed of the collision) a speed strictly greater than 11.2 km/sec.
If you really want to understand this further, here is a physics book where it is explained, between chapters 3, 4 and 12:
http://www.phy.duke.edu/~rgb/C...
rgb
Asteroids will hit the Earth (if at all) at LEAST at 11.2 km/sec, as they have greater than escape energy relative to the Earth's gravitational field. That's 11.2 kilometers per SECOND, or a bit over 40,000 kilometers per HOUR. The energy released is greater than 64 million joules per kilogram of rock (escape energy). So if you take a (say) 2.5 km ball of rock (5 km in diameter), roughly estimate its mass as 4 times r^3 you get 4 e+18 joules. Convert this to tons of TNT and you get roughly a teraton. The total explosive energy of the entire nuclear arsenal of the Earth is less than 7 gigatons (including reserve weapons -- only around 1 GT is on delivery vehicles almost all of this belonging to the US and Russia). The biggest explosion in recorded history was the explosion of Tambora in 1815, estimated at 33 GT. This is then equivalent in crude terms to over 100 times the entire global arsenal nuclear and conventional, or over 30 times the explosive power of the largest explosion in recorded history, one that altered global climate for close to a decade. Or GREATER.
I'm not sure "hit by a bus" is an apropos metaphor.
Even worse, pretty much every science fair project has to have a conclusion to get anywhere. Teachers don't let kids run an experiment where the conclusion is that the test didn't have any findings that support accepting or rejecting the hypothesis. That is not only a perfectly acceptable result in science, but a very good one to find.
Hear hear! I'm giving up a chance to mod you up because that isn't sufficient. This is all by itself one thing that is wrong with STEM training from the beginning. One cannot just build a telescope or Tesla coil -- both pretty ambitious, amazing projects for any science fair -- you have to have a HYPOTHESIS and you have to PROVE IT because, I dunno, null results are so boring and indistinguished that they will never win. Kids learn at Science Fairs that if they don't prove their hypothesis no one will look twice at their work no matter how nifty and then we wonder why twenty years later they are falsifying data or engaging in data dredging or cherrypicking to get publications to get tenure or keep a grant. We also wonder why we get a steady string of crappy papers on things nobody really cares about -- but which have clear targets likely of success -- instead of a few bold papers where the researchers took risks at finding nothing equal or greater to the chance of finding something. Those big, risky topics are career killers unless you are fortunate enough to have nearly independent "means" as research support.
Don't get me wrong -- evidence is key to directed Bayesian beliefs, and science should teach the importance of evidence. But the entire Enlightenment wasn't driven by hypotheses eventually supported by evidence. It was driven by bold, amazing new instrumentation -- for example, microscopes and telescopes -- that opened up a Universe of new data at the macrocosmic and microcosmic levels Pure observation based on these new instruments eventually LED to hypotheses, and as time passed the successful hypotheses were woven into an ever tighter tapestry of evidence supported beliefs connected to other evidence supported beliefs and the scientific worldview. This was equally so for most of the initial work done with electricity and magnetism -- people built nifty generators and studied the effects of electrical currents and then, eventually, built a mathematically rich explanation of the collective set of observations.
Can you imagine having to formulate Maxwell's Equations as a hypothesis ALL AT ONCE and then going into a laboratory to try to verify them? Or even something simpler, like Coulomb's Law? Hell no! Coulomb may or may not have suspected that electrostatics were going to be "like" gravitation (although Newton had no compelling reason to choose 1/r^2 for gravitation in the first place, lacking Gauss's Law or any equivalent thereof) but the evidence in favor of it was compelling and immediate.
Cutting edge real science has observations leading hypotheses -- as, if you think about it, it usually should -- more often than not. But high school science teachers and the founders of the whole idea of "science fairs" have completely lost track of this in their eagerness to teach The Scientific Method as religion instead of a practical methodology that -- eventually -- needs to be satisfied.
Well, not "get fucked", surely...
Ultimately it is an empirical question but it is an unusual one. The problem with looking only at locality in a single direction of time flow is that the underlying microdynamic propagators are (without exception as far as I know) reversible in time. My favorite example of this is in classical electrodynamics, where we CHOOSE to use retarded propagators, but where one can equally well formulate things in terms of advanced propagators and where Dirac did an amazing job of deriving radiation reaction theory using a mixture of advanced and retarded propagators (further supported by Wheeler and Feynman and the perfect absorber derivation which in turn is connected to Lindblad and master equation formulations of quantum theory).
This is where IMO it is very difficult to understand Bell's theorem. It seems to require forward (retarded) time only, but if one allows for advanced time as well as retarded time both operating simultaneously, the paradoxes disappear. It becomes literally impossible to hide the future state of the ultimate absorbers of any e.g. photons emitted from a quantum entangled system from the emitting system -- the entire path through all intermediate filters is NOT information that is unavailable to the emitting system. The real problem is that that the time evolution of a closed quantum system begun in a stationary state is stationary, period, from a very fundamental theoretical level. The "paradoxes" seem to arise when we try to create "observers" that are one part of the total system, "systems" that are another part of the total system, and a "bath" made up of everything else that is in an almost completely unknown state. EVERYTHING is fully quantum entangled, ALWAYS. But when you split things up, pseudoentropy appears as one is forced due to ignorance of boundary conditions and intermediate time evolution of the whole to use a statistical (and hence classical or at worst semiclassical) description of both bath and observer.
It's pretty easy for me to believe that the effective pseudoentropy of Universe-(sub)system is so absolutely enormous that the quantum description of any subsystem (averaged) is going to look "random" in accordance with Bell's inequality but not, in fact, be random. It isn't a matter of local hidden variables, it is a matter of unknown state variables in everything else coupled to the system by ordinary interactions.
My journey has been longer, padawan. But you are mistaken: we do have both hover cars and hover boards. They are just expensive and dangerous. What did you expect? Antigravity? Suspension of the laws of physics? Personally I was hoping for antigravity capable of floating a car-sized mass with a tiny trickle of current, reorientable as a gravity-based drive. But somewhere back in the 70's and early 80's I finished my physics degrees and alas, there was no plausible antigravity anywhere to be found. Still isn't. Especially one that would work on a first-law-violating trickle of current.
Sigh.
And peel back the paper to expose the powder and use a nail to pop it directly. And string them together to make a fuse. And... yeah. Good times.
I too, can't understand why anybody would ever get a spinner. At first I thought they were a version of gyroscopic wrist trainers:
https://www.amazon.com/dp/B01F...
that required a "trick" to keep moving, but ten seconds of examination and experimentation revealed that they are not. And gyroscopic wrist trainers are already pretty boring, but at least there you have to "do" something and you can fix them up with pretty lights and so on too. Spinners aren't even a good meditation aid -- they demand exactly the wrong kind of attention to keep going and they are not a useful focus.
If something has a cause, then it can be predicted and patterns can be identified. It is not random.
Except that there are phenomena that cannot be predicted. Even ones we know are not really random. Then there are quantum phenomena that MAY be really random. You are making a religious statement when you assert Universal causality as a definite truth instead of a conditional probability. And lack of evidence is not evidence of lack -- the best you can say is that it might make something less probable within certain bounds.
I agree that the Universe PROBABLY is causal and in a zero entropy state, because we have little definite evidence otherwise (time-irreversibility of things like Kaon and B decay aside, a few experiments that claim to demonstrate "true" quantum randomness aside). But according to science this is an empirical question, not a religious one. You might as well assert that as far as we know, it IS possible for true randomness to exist.
On the empirical note, if you are presented with a string of data, perform any and all tests on it that you like, and cannot prove that it is NOT random, what exactly is that evidence of? Please do not invoke religion in your answer such as a belief in causality, as that just begs the question. That's precisely what you are doing if you assert that quantum phenomena at a certain scale are not random. Maybe not, but we have no model that predicts them, we have theories that suggest that no model CAN predict them, when we examine them for randomness they appear random. The arguments (such as the arguments that lead to the Master Equation description of quantum phenomena) that allow for it to be otherwise are difficult and while they may be correct, it is far from certain (empirically) that they are.
As I posted above, we do not know this. IF you accept e.g. the holographic MODEL of string theory, then there is no entropy even at the quantum level. On the other hand there are plenty of articles in QFT that discuss the possibility that QFT is truly irreversible at some level so the direction of time is not just a consequence of entropy.
It is perfectly fine to think that one or the other of these is "more likely" to be true on the basis of what one knows or guesses, but because physics is not religion it is not appropriate to state that there is not random as a proven fact, that the entropy of the Universe is zero and there are no true entropy sources. Ultimately this, like everything else, is an empirical question.
Personally I agree with you and think that whether or not the holographic model per se is correct, QFT is probably reversible and that the Universe is in a zero entropy (definite) state with no "outside" source of entropy to make it non-deterministic on the basis of internal dynamics alone. But in the end, experiments talk, bullshit walks and even the sexiest theoretical model is bullshit until it is confirmed by experiment.
There are three meanings of the word "random" referring to a generator in this context:
a) Unpredictable.
b) Empirically satisfying all of the decorrelation properties of a random number sequence -- on average uniform in all bit patterns, on average lacking correlations at all lags (and hence non-periodic) and on all N-dimensional hyperplanes for all N, etc.
c) Both.
All that is asserted here is that they have a thermal noise generator that satisfies a). Big whoop -- thermal noise generators (and hardware generators in general) are commonplace: https://en.wikipedia.org/wiki/.... However, thermal noise and so on are often "colored" or "biased" -- they produce fluctuations that are unpredictable but it is almost impossible to get the noise to produce a string of e.g. 0's and 1's that satisfy b). One then is stuck using the unpredictable noise to randomize a pseudorandom number generator (for example, by xor'ing the two together) that produces a bit string that has the right uniformity and decorrelation properties but does so from an internal state that, if known, makes the string produced predictable.
AGAIN this sort of thing is pretty commonplace. Sources of "entropy" as in unpredictable activity are common enough and so are high quality pseudorandom number generators. The major problem then is rate. Few of the hardware generators can produce entropy FAST ENOUGH to keep up with a PRNG, so getting a source of "true random numbers" that is fast enough to use in e.g. Monte Carlo is not easy, and most people don't bother to try. Having a handful of unpredictable numbers suffices for e.g. encryption and that's really where this is headed.
I would wax poetic on the fact that EVEN thermal noise is probably not truly random; it is random the way a coin flip is random or, for that matter, the way a PRNG is random. The outcome of a coin flip is unpredictable only because we don't flip the coin with a precise knowledge of its state and the state of the flip environment and because we perhaps cannot integrate its equations of motion precisely enough from what knowledge we do have, but it is deterministic, hence not really unpredictable. Classical thermal noise is no different than a bunch of flipping coins bouncing around -- again deterministic but with lots of unknown state information. "True" random is a term that should probably be provisionally reserved to AT BEST quantum "coin flips", although in the master equation approach to resolving the state of a quantum "coin", the true origin of randomness is seen STILL to be the process of taking the trace of the surrounding environment, which is if you like the filter resolving the flip. That trace introduces "entropy" in the form of lost phase information and averaging over energy distributions that appears as unpredictability in the outcome, but if one views the "coin" AND the surroundings as a single quantum system its quantum trajectory is again deterministic. Randomness in quantum filtering experiments comes from the fact that the measuring apparatus that does the filtering must resolve it in a classical was with its quantum entangling and phases in general unknown and averaged over.
If one buys the holographic model in string theory (or plain old quantum theory as it is currently structured) the Universe is in a zero entropy state and there are no sources of "real" entropy. In this case there can BE no "true" random number generators. Whether or not nature is capable of generating true random numbers from some source other than our ignorance of state is an open empirical question.
Coal can be turned into gasoline and has been since at least World War II.
I'm sure that they wash the coal carefully before using it. No more dirty coal!
...for a narrow time window. The moon gets a bit more than 3 cm farther from the earth every year due to rotational energy coupling through the tides. We are in the comparatively narrow time window (geologically speaking) where the moon and the sun have roughly the same angular width as seen from the earth (depending on just where the moon is in its elliptical orbit and where the earth is in ITS elliptical orbit). Wait a million years or so and the moon will produce only annular eclipses.
It's like Polaris as the North Star. Fiction writers like to portray Jesus or Moses or Caesar looking north and waxing poetic about the Nort Star, but a couple of thousand years ago Polaris wasn't the North Star, we had no North Star. Even a few hundred years from now it is going to be making circles instead of behaving like a fixed point on time lapse photographs. Sigh.
Even then, the protons would be contaminated with electrons, gluons, neutrons, etc. It will be much harder to fill a bucket with pure protons.
I was going to mod this funny, but then I thought "No, nobody will understand the joke..." Much harder, snort mrrf, har har har.
A point I was making way back then, when it wasn't even cost effective. If the US had invested (say) 20 or 30 billion a year directly into photovoltaic power starting back in the second Iraq war, let alone the first, by guaranteeing a market they would have singlehandedly created the solar cell manufacturing capacity to utterly dominate the world marketplace, they would have dropped prices at 2-3 times the rate they ultimately dropped anyway, and by now we would made the Middle East and its oil supply even more irrelevant than they are rapidly becoming.
This is one thing nobody is even noticing, even though it is ongoing. We're in the last decade where oil is going to be "valuable" as a fuel. Saudi Arabia is going to undergo a profound, deep, economic crash. Most of the Middle East and other oil producing countries (and companies) are going to be right in there crashing and (not) burning. Oil will be a lubricant and important chemical stock, but burning it for the most part will stop making sense and existing stocks will plunge in price. One major casualty of this will be Russia. Tillerson is such an appallingly transparent choice for SecSt, as he personally will be another. At this point it is too late to put the genie back into the bottle, even though the government by its stupid choices as kept it jammed in there as long as it possibly could, as we are at the pivotal point where one can take a house off grid "forever" for less than the cost of a high-end car in most of the US (the lower states, certainly). And it is only going to get cheaper. A lot cheaper. Fast. Much faster than the pundits themselves seem to realize.
I expect to see ten cents per watt-hour of high-end battery storage well before 2020. A 50 KW-hour whole house battery plus regulator for $5000, sized to fit easily into a dedicated function closet. Even just used as a whole house UPS and energy brokerage tool you'd probably break even on that -- buying electricity and charging at cheap/low demand night to run your AC in high-demand/expensive daytime, being invulnerable to up to 24 hour line outages during storms, buffering line surges -- but you can ALSO use as much or little renewable capacity as you can afford to charge it up and reduce line demand. We're teetering on 10 year amortization right now, but we'll see 7 year amortization by 2020. Borrow the money, install a full off-grid system (that sells back to the utility if there is surplus, sure) and pay for the whole thing in 7 years while dropping your monthly power bills even while paying it off.
At that point, the government is irrelevant except to get out of the way and not try to prop up the doomed utilities by imposing legal obstacles.
So a better way to put it is that it is order of one CUBIC mile. You can make the cross-section smaller by making the stack higher or vice versa. Area measures make sense for solar cells. They don't for batteries.
They REALLY don't for batteries that are supposed to back the whole solar grid for the US. Those batteries generate heat as they operate -- charging or discharging. If you actually built a solid battery a cubic mile in volume (say) heat losses scale like the outer radiating surface, heat production scales like volume. Even very modest losses would rapidly raise the temperature of the center of the cube to the point where (resisting the temptation to say something hyperbolic such as "thermonuclear fusion occurs" the "temperature of the surface of a star" etc) but honesly, the latter is probably true -- 6000 K would be quite reasonable if it weren't for the fact that the entire stack would melt and fail long before that.
If you build the batteries of a size that can self-cool via convection/radiation -- no active cooling required with larger radiators or heat exchangers -- and assign them a reasonable margin of empty space around so that they don't overheat -- they would occupy far more than a cubic mile, and with an average height order 1 meter, they'd occupy tens to hundreds of miles square of total area. That is hundreds to thousands of square miles
So let's forgive EM his usual hyperbole and sales pitch exaggerations. Nobody is going to actually build this in this way, and as noted above, this argument is so old it is positively ancient. The critical number, which he omits, is that if we assume that the US uses roughly 10 terawatt-hours/day, and assume that we can generate this with around 3 terawatts of of (peak) solar capacity plus storage in an average day, and solar power costs roughly $1/watt (peak) installed, then it would cost roughly 3 trillion dollars to install all of this electrical capacity at current prices, give or take a factor of two -- there would be economies of scale to a massive project like this, for example, but the duty cycle (average) of the cells is arguable and average solar constant as a function of location is variable, so one might need twice this capacity to have some margin. With a population of three hundred million people, we could buy this for ten thousand dollars each, and the investment would be amortizable against the savings in electrical energy costs already extant (typically amortizes in 10 or so years of a 20+ year expected lifetime).
This lets one instantly at least estimate scenarios. $1000/person is $300 billion. If we invested $1000/person/year, at a cost of $300 billion total, 100% provided by taxes (as poor people cannot afford $1000/person/year, and rich people actually consume a lot more on average of the energy this would generate to boot, both personally and in their corporate rents and ownerships) we would completely remake the country's infrastructure in ten years, very likely getting to the point where all we'd need is bridge power from a network of e.g. nuclear power plants and a gradual investment in increased and replacement capacity (generation plus battery backing) to never have to actually BUY electricity again. We could actually charge "energy taxes" at cost of this maintenance plus new growth at cost based on individual and corporate consumption and enjoy the closest thing to free energy solar can deliver at any given level of technology and development. We could charge energy taxes AS our tax basis, eliminate income taxes entirely, and distribute the cost burden of government proportional to energy consumption, both per capita and corporate. If you want to go off grid, you won't have to pay taxes, except that anything you buy or use that is even MADE with energy will have a hidden tax in it. Maybe it would work, maybe not, but it is an interesting idea, akin to a "gold standard" except that the unit of commerce would de facto be the joule (or KW-hour, or whatever).
We're well on our way to this
I WAS kidding, right? Although SF (e.g. Oath of Fealty, Niven and Pournelle) speculates on towing medium sized icebergs for just this purpose (providing fresh water in a water-scarce zone). But yeah, an iceberg the size of Delaware, or whatever metaphor for a 50x40 mile chunk of area many meters thick you would prefer to use, would be rather expensive to move.
What will be interesting will be if it floats north. It's big enough to significantly cool a good sized chunk of sea surface as it melts, at a guess. This, in turn, might affect many things in good and/or bad ways. For example, interrupting or diverting the thermohaline circulation would be "interesting"...
10K years old
...12K years old...
Fixed that for ya. I assume that you mean the end of the Wisconsin glacial epoch, give or take a Younger Dryas. Funny how human civilization rose during a period of intense global warming... (and the melting of an ice layer several kilometers think that covered most of Canada and much of the northern US at the time...).
Archeological studies suggest that there was a serious political conflict back then with the "whites" -- a combined ecological-political movement that opposed the (obviously human induced) climate change -- and the more progressive "greens" who viewed climate change as an obvious opportunity to make a huge profit on suddenly desirable real estate, at least until it was swamped in the 100-odd meter sea level rise associated with the change.
Sadly, throwing entire populations into volcanoes and cutting the hearts out of thousands of slaves proved to be inadequate to prevent the climate change, although the Younger Dryas was evidence that if the population of the world were just a LITTLE larger at the time, mass genocide might have accomplished it, and we'd still have woolly mammoths along with woolly socks.
So, let's tow the iceberg to the Sahara, and use it to irrigate and cool the desert, and in the process bind up much of the water in an extension of water cycle to lots of surface area that currently does not participate. No? Just because it will cost a trillion dollars or so? When did costs become an important part of the climate narrative?
As I sit here, preparing to teach electricity and magnetism (having corrected a minor error in the electrodynamics book I wrote to help supplement Jackson while teaching graduate electrodynamics, I do find it interesting that you ignore the actual algebra I put into my previous reply and instead attempt to argue using logical fallacies. Most of the Wikipedia articles on physics are, in fact, pretty damn good, and photons are considered "massless" particles in pretty much every physics textbook that considers them, where yes, the term refers to their rest mass but also where there is no real point in considering them to be massive in any other context and some serious inconsistencies to deal with when one tries to treat e.g. h\nu/c^2 as if it is a "mass" as far as gravitation is concerned.
A nice discussion of the latter is here:
https://physics.stackexchange....
And yet another article (containing many links to actual references) on the standard model in which the photon and gluon are indeed massless particles is here:
https://en.wikipedia.org/wiki/...
again with many references, such as almost any textbook in physics that addresses the issue at all.
Perhaps you could stop accusing people of ignorance and asserting that WIkipedia is written by idiots and instead provide an actual reference to a textbook or article in a peer-reviewed journal where it is claimed, with evidence, that it makes sense to associate a mass with a photon, even in the context of gravitation (where there is indeed a gravitational interaction with its ENERGY).
E = \gamma m_0 c^2 for massive objects, where m_0 is their rest mass. Alternatively, E^2 = m_0^2 c^4 + p^2 c^2. In neither case do electromagnetic waves have mass. Indeed, for electromagnetic waves (or photons) E = pc because m_0 = 0. This does NOT mean that E = \gamma m_0 c^2 = pc = m c^2 with m_0 = 0 and \gamma = infinity (where you effectively have to assert that 0 * infinity = 1) so that you can conclude that p = mc for electromagnetic waves for some meaningful/useful definition of mass. Note well that one cannot just assert that 0*infinity = m (for some specific, varying, value of m!) in the first place as a useful step in algebra, and there is no good way to take limits of m_0 \to 0 and v \to c to define an "asymptotic" massive electromagnetic wave of photon, at least that I've heard of.
Either way, U(1) symmetry requires the photon to be massless, classical electromagnetic theory requires electromagnetic waves to be massless, experiments have restricted the (rest) mass of photons to be less than 10^{-18} or so kg, and \gamma is not a meaningful construct for objects with zero rest mass that propagate at the speed of light.
Finally, to rebut the various people who WANT to make m = p/c for a photon or assert that it is not a massless particle, I quote the wikipedia page for massless particles:
In particle physics, a massless particle is an elementary particle whose invariant mass is zero.
That is, by definition the invariant mass of a photon is zero -- it is a massless particle. In fact, it is the first example of a massless particle given on this page, along with gluons and gravitons.
So please, can we stop accusing people who assert that the photon is massless of being ignorant or stupid or not understanding physics. If anything, quite the contrary.
Yeah, but I'm a physicist and am not affiliated in any way with Duke Power. I'm just stating facts -- indeed, here is a piece of DP information:
https://www.duke-energy.com/ou...
700 large scale solar facilities around the state. What they are doing in other states I do not know, but in NC they are literally building new ones all the time. Note this:
http://www.seia.org/research-r...
NC is indeed number two in the national rankings in installed capacity as of last year, behind California and (perhaps surprisingly) ahead of near-desert states like Arizona, and most of this is Duke Power.
I reiterate: The Koch brothers have a specific agenda that is (as far as one can tell) the active suppression of democracy and the establishment, no, that's not fair as it's already there, the rapid growth in the power of an oligarchy. The energy companies in general, however, don't give a rat's ass what is the source of the energy they collect or release and redistribute, as long as they make a good profit from it. Solar is profitable, and about to become the most profitable, by far. So it doesn't matter what one does to "free up coal" or reverse carbon restrictions. Nobody is going back to (substantial new capacity in) coal in the US, although it may be decades before the grid can function without it.
Hey. don't pick on Duke Energy. NC is something like second or third in the nation in terms of total solar installation, and Duke Power is installing them pretty much everywhere. It is getting difficult to drive a hundred miles on major roads without seeing at least one solar farm off to the side of the road.
You are mistaken if you think that solar energy somehow costs the big electrical power companies profits. Quite the contrary, quite the contrary. PRIVATE solar rooftops might one day cost them profits, but solar that they install themselves makes them money. It is cheaper and easier to finance incremental installations of solar than it is to permission, finance, and build pretty much anything else.
--If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
Hmmm, interesting analogy. I don't think I agree. If construction were like programming, many buildings would have corridors that wind through the building with no entrances, it would have others with one way doors that you enter on the ground floor that take you through corridors with no exit to the top floor and exit through a one way door into thin air, it would produce buildings intended to function as a public library where the books have to be brought up, one at a time, from a basement filled with rooms indexed with the first word of the title and shelves indexed with the second stored in the order of the third word per shelf, for books with three or more words in the title. An entire second layer of basement would contain similar rooms indexed by the first letter of the author's name, etc, where the only items in card catalogs are the titles (hence first three words) in each author's name. An incorrectly fitted lock is more like a syntax error or typing error in a program -- comparatively easily found and corrected. Even if the lock is the primary entrance -- so it DOES block the use of the building -- the building doesn't "crash" as in have to be rebuilt, it just needs to have the lock fixed so that the building can be used.
In other words, there are plenty of places where the analogy does work. If you build a building with inadequate structural members, it might WELL come crashing down and have to be redesigned and rebuilt. If you build a building that is too small or too poorly designed to fulfill its primary function, whether it is as a residence or business or manufactory, you might need to tear down and start again, or do "extreme remodelling". All of those ARE features of coding as well.
I'd be more inclined to say that construction, or engineering in general, are a lot more like coding than not like it. Engineers build machines, or buildings, or bridges, out of structural elements that have properties, purposes, and that follow a certain logic. Coders build "machines" out of words. Special words, no doubt -- words that are structural elements with properties, purposes, and that follow a certain logic -- but words. That's the main difference.
To bring the (gentle, I hope) philosophical rant above back OT, serious coders are those that build their first machine out of words and then say to themselves how cool was that! At that point, to my own direct experience, you can't really stop them, especially if they learn that they can get material rewards for doing it as well. They will teach themselves what they need to know to pursue their (a)vocation, they will scrounge resources, they will stay up late (the only time you can code is late at night when all of your life 'distractions' have gone to bed:-), neglect their personal hygiene, and start drinking Jolt Cola to maintain their edge when they have to function in the "real world" on four or five hours of sleep in order to get 6 to 8 uninterrupted hours to code.
Personally, I think that the death of the US coder was caused by Windows and the various post-Mac Apples. PC-DOS provided a built in path for computer owners to start to write programs -- the original IBM PC has BASICA in ROM so you couldn't own a computer without owning at least one programming language in its own "development environment". BASICA got dropped from ROM as clones appeared, but it was replaced by "turbo" compilers that were cheap IDEs that anybody could buy (and did) driven by the fantasy of writing a game or killer app for the platform. Then Windows came along, and it was no longer easy, or cheap to write a program with graphics. This raised a huge barrier between the kids who might have become hackers/coders and actually doing so. At this point NO laptops or desktop computers sold with pre-installed Windows have anything like programming support.
This means that the only platform in the
Or all three at once! And don't forget sex!
No, it's just that well over half of us live in an enormously neurotoxic environment -- heavy metals in the water and air, food additives, insecticides, hormones, and antibiotics in the food, radioactives in the buildings and soil leftover from the era when we deliberately exploded nuclear bomb after bomb upwind of our population centers and farming regions. Then throw in Television, to take the brain-damaged children and ensure that they never even have to learn to read properly to be entertained at the same time they learn that entertainment is sitting passive (and has no intellectual challenge whatsoever in 95% of what is considered "entertaining"). Feed those children fast food with a huge salt load, sugar load, and a lack of actual nutrients so that -- given their sedentary entertainments -- they all are slightly overweight as children and blossom into openly fat adults long before "their time", impacting the blood supply to their brains. These children are taught -- explicitly taught -- not to think too critically from when they are far too young to resist, as a part of learning a religion that was literally invented and perfected to make a slave population content with their lot and unwilling to act to change it in an enormous slave-based empire in the fourth century BCE and that has done its work superbly (both functions -- elimination of critical thought and contentment with slavery) forever after. To finish off the job, put them in public schools with teachers that "Don't know where Malta is", being taught math by people who got a B- in calculus in college (if they went to college) from a textbook selected by a committee whose sole virtue is that it MIGHT help teach the students to balance a checkbook by the time they get out of school -- if there were any such thing as a checkbook any more.
Is it any wonder that at the end of this, you end up with young adults that think that the National Enquirer and Globe are the best sources of news and who vote for a billionaire liar serlal philanderer as president as being the best possible choice for freeing them from all of the massive corporations (including his) for whom they are a nearly perfect source of cheap labor? Note that it isn't any one of these things, or two of these things -- people can shrug off malnutrition, they can get past a terrible education -- it is literally damaged brains (probably in utero) as evidenced by the steady rise in ADD, ADHD, anxiety disorders, suicides, and more among the young and young adults, TOGETHER with a 60% or better terrible education with poor teachers and miserable textbooks, the elimination of reading as the primary form of "fantasy" entertainment (fun obtained from something other than getting up and doing something outdoors, with others) so that they cannot easily teach themselves, an information stream provided for entertainment that could cause brain damage (of sorts) in full grown adults, etc.
We shouldn't forget the impact of PTSD and rampant cigarette smoking, alcoholism and drug abuse among the young (including the very young) as well. At least those are things that the US doesn't have a near-monopoly on. The amazing thing is that even with all of this, a remarkable number of children grow into functional and even intelligent, ambitious, competent young adults. And we make up for many of the losses by attracting the best and brightest people from all over the world to immigrate and fill in the positions it is difficult to fill out of our general population, and it usually takes a generation or two for the genetic and cultural/moral decay to set in.
As for the Russians -- it is easy to see why they become hackers etc. A large chunk of Russia is too dark and too cold to go outside in winter at times that they aren't in school. Kids therefore have to entertain themselves indoors for months at a time at least during the winter. Russian TV sucks and is a lot sparser than US TV, and once they've read all of the books in the house, nothing is left but the computer(s). The r